The MFL3 monoclonal antibody reacts with mouse Fas (CD95) Ligand, a 40kDa type II transmembrane glycoprotein. FasL is a member of the TNF family and is expressed by mouse activated T cells. The interaction of FasL with its receptor CD95 induces Fas-mediated killing. It has been reported that the human FasL antigen is cleaved from the surface by matrix metalloproteinases (MMPs), resulting in a 26kDa soluble form. The degree of sensitivity for the mouse antigen to MMPs has not been reported.